You need to deregister your fingerprint first in settings>finger scanner>fingerprint manager by swiping your registered finger or entering the backup password before you can delete it. It worked for me.

got it you go to Settings > Security > down to Clear Credentials and select it. Then go back to Lock Screen and it will be available. then choose swipe. back to normal. also, the dang backup password all missed up.

Hi, if you are looking for unlocking your phone by means other than Fingerprint (swipe/pattern etc) then here is what you need to do.
Settings> Finger Scanner> under Features, select Screen Lock. It will ask you to swipe your finger over the home key. Do that and then select the unlock method of your choice. Hope it helps. Cheers!